npm install --save bcrypt

var mongoose = require('mongoose'),
 Schema = mongoose.Schema,
 bcrypt = require('bcrypt');var UserSchema = new Schema({
 username: { type: String, required: true, index: { unique: true } },
 password: { type: String, required: true }
});
module.exports = mongoose.model('User', UserSchema);

let SALT_WORK_FACTOR = 5
UserSchema.pre('save', function(next) {
 var user = this;
 //产生密码hash当密码有更改的时候(或者是新密码)
 if (!user.isModified('password')) return next();
 // 产生一个salt
 bcrypt.genSalt(SALT_WORK_FACTOR, function(err, salt) {
  if (err) return next(err);
  // 结合salt产生新的hash
  bcrypt.hash(user.password, salt, function(err, hash) {
   if (err) return next(err);
   // 使用hash覆盖明文密码
   user.password = hash;
   next();
  });
 });
});

UserSchema.methods.comparePassword = function(candidatePassword, cb) {
 bcrypt.compare(candidatePassword, this.password, function(err, isMatch) {
  if (err) return cb(err);
  cb(null, isMatch);
 });
};

var mongoose = require('mongoose'),
 Schema = mongoose.Schema,
 bcrypt = require('bcrypt'),
 SALT_WORK_FACTOR = 5;
var UserSchema = new Schema({
 username: { type: String, required: true, index: { unique: true } },
 password: { type: String, required: true }
});
UserSchema.pre('save', function(next) {
 var user = this;
 // only hash the password if it has been modified (or is new)
 if (!user.isModified('password')) return next();
 // generate a salt
 bcrypt.genSalt(SALT_WORK_FACTOR, function(err, salt) {
  if (err) return next(err);
  // hash the password using our new salt
  bcrypt.hash(user.password, salt, function(err, hash) {
   if (err) return next(err);
   // override the cleartext password with the hashed one
   user.password = hash;
   next();
  });
 });
});
UserSchema.methods.comparePassword = function(candidatePassword, cb) {
 bcrypt.compare(candidatePassword, this.password, function(err, isMatch) {
  if (err) return cb(err);
  cb(null, isMatch);
 });
};
module.exports = mongoose.model('User', UserSchema);

var mongoose = require('mongoose'),
 User = require('./user-model');
var connStr = 'mongodb://localhost:27017/mongoose-bcrypt-test';
mongoose.connect(connStr, function(err) {
 if (err) throw err;
 console.log('Successfully connected to MongoDB');
});
// create a user a new user
var testUser = new User({
 username: 'jmar777',
 password: 'Password123'
});
// save user to database
testUser.save(function(err) {
 if (err) throw err;
 // fetch user and test password verification
 User.findOne({ username: 'jmar777' }, function(err, user) {
  if (err) throw err;
  // test a matching password
  user.comparePassword('Password123', function(err, isMatch) {
   if (err) throw err;
   console.log('Password123:', isMatch); // -> Password123: true
  });
  // test a failing password
  user.comparePassword('123Password', function(err, isMatch) {
   if (err) throw err;
   console.log('123Password:', isMatch); // -> 123Password: false
  });
 });
});